Thanks to your example I was able to 'pin-point' my problem and I have found my solution.
You were right, this is not a bug in the library it was my very own application that was causing this trouble.
The problem was that other processes for whom I had created the local port forwarding, kept one end of the port open. (In my case adb.exe, android debug bridge).
The solution is to first close these processes before stopping the forwarded ports. Now stopping is completing fast and successfully.
Thanks for the great support and sorry for the inconvenience.
You were right, this is not a bug in the library it was my very own application that was causing this trouble.
The problem was that other processes for whom I had created the local port forwarding, kept one end of the port open. (In my case adb.exe, android debug bridge).
The solution is to first close these processes before stopping the forwarded ports. Now stopping is completing fast and successfully.
Thanks for the great support and sorry for the inconvenience.